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instead Q rudimentary like those of other "Whales, the blow-
hole lies more in the middle of the face. The skull, too, is
not "Whale -like in. a number of other points. Thus the pre-
maxillaries take their fair share in the outline of the upper jaw ;
and, furthermore, bear the incisor teeth. The parietals meet
above in a crest and are not excluded from the roof of the
BkulL The vertebrae of the neck are in no way shortened ;
neither are they fused together. The ribs are double-headed, and
the sternum is made up of several pieces. Some naturalists,
particularly Professor D*Arcy Thompson,1 have assigned a relation-
ship to the Seals to fcliese ancient Cetacea ; but others2 have
disputed this view chiefly on the grounds that the characters
"which appear to be Seal-like are simply characters which, are
generalised and so far at most not "Whale -like. Thus the long
neck and the serrated character of the teetli may be accepted as
Seal-like on the one hand ; but on the other, a simple serrated
tooth and a long neck are not by any means features of organisa-
tion which, we should, consider out of the way in an ancient form
of Cetacean \vhich probably preyed upon fish. The humerus of
Zeuglod-on, according to Mr. Lydekker, puts out of court any
possible near relationship to the Seals. But the matter under
dispute can be further studied by reference to the three memoirs
quoted below.

1 Thompson, Studies Jftut. Dundee, L 1890 ; and C. JR. C*m@r&8 de Z&ol&@if 1889,
p. 225,

s Lydekkor, Proe. Zool. So-c. 1892, p. 560.